gismo
Yes, that is correct.
The OTA process runs via the OTAQ updater from Dudu, which checks the registered id.
The "old school" method where you unpack it to USB and remove the updatecfg.txt is using the standard rkupdate and lsec6318update from FYT via the recovery. That always works.
But of course you do get the "first time startup wizard", which you do not get when using the offline OTA method.